Eco-friendly synthesis of bimetallic AuAg nanoparticles

Author(s)

Garcia, Amanda G. ^[1] ; Lopes, Pietro P. ^[1] ; Gomes, Janaina F. ^[1] ; Pires, Cleiton ^[1] ; Ferreira, Eduardo B. ^[1] ; Lucena, Rubens G. M. ^[2] ; Gasparotto, Luiz H. S. ^[1] ; Tremiliosi-Filho, Germano ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Rio Grande do Norte, Inst Quim, BR-59072970 Natal, RN - Brazil

• Document type: Journal article
• Source: NEW JOURNAL OF CHEMISTRY; v. 38, n. 7, p. 2865-2873, 2014.
• Web of Science Citations: 29

Abstract

In this study we report a friendly route to produce colloidal AuAg bimetallic nanoparticles (NPs) using glycerol as a reducing chemical in alkaline medium. Ultraviolet spectroscopy (UV-Vis) and transmission electron microscopy (TEM) confirmed the formation of colloidal NPs. The nanoparticles were also directly produced on carbon to yield Au/C, Ag/C and AuAg/C. Extended X-ray absorption fine-structure (EXAFS) spectroscopy at the Au L-3 edge evidenced surface segregation of silver in the AuAg/C material. Also the X-ray absorption near edge structure (XANES) region indicated a slight reduction in the Au 5d band occupancy due to the presence of silver. Since a fuel cell is a potent source of energy for the future, the catalytic properties of the NPs were investigated for anodic glycerol electro-oxidation reaction and results for AuAg NPs are compared with those for monometallic Au and Ag NPs. When compared with Au/C, the AuAg/C material displayed lower potential for glycerol electro-oxidation, reducing by 120 mV the onset potential for glycerol electro-oxidation. This means that the electro-oxidation of glycerol on the bimetallic catalyst is mainly affected by the ligand effect. (AU)

• FAPESP's process: 12/10856-7 - Investigation of the mechanism of glycerol electro-oxidation on metallic nanoparticles
• Grantee: Amanda Cristina Garcia
• Support Opportunities: Scholarships in Brazil - Post-Doctoral